(see related stories on taxes, Berlusconi) Pontida, June 17 - Silvio Berlusconi on Monday said that the doubts Premier Enrico Letta's government has expressed about its ability to cut an unpopular property tax and avert a 1% rise on value added tax scheduled for July were "unacceptable". Berlusconi's People of Freedom (PdL) party is supporting Letta's left-right government but it has threatened to sink the executive if it does not scrap the IMU property tax and return 2012 revenues from it to respect a pledge made in the campaign for February's general election. The centre-right party also wants to avert a rise in the top band of value added tax (VAT), from 21% to 22%, that is scheduled for July after being put in place by former premier Mario Monti's technocrat administration. But Economy Minister Fabrizio Saccomanni has suggested it may not be possible to scrap IMU and stop the VAT increase, saying this would leave an eight-billion-euro hole in the budget. "It's unacceptable," Berlusconi said at the opening of a clinic. "The government is struggling to find eight billion, but what company cannot cut its costs by 1%? "IMU is a damaging, unjust tax. We want it abolished, almost as a symbol of the State making peace with the public. "(As for VAT) the economists who have their heads on their shoulders say that it would not generate greater revenues for the State but reduce them".